Here is the simple solution. Award points based on participation. Reduce rewards for losing and slightly increase them for winning.
Right now there isn't much difference in rewards for winning or losing so there is no incentive to win. That's partly why we have the shields down kamikaze assault going on. Change those two simple things and the problem will mostly solve itself.
For extra incentive, have a match MVP declared at the end based on participation not just damage and award that player a small bonus.
Cloak griefers will become common, get to 14 kills with a good lead, cloak up for an hour or two watch something and still level as quickly as playing non stop.
A reason why tickets or objective based games are superior to simple deathmatches in space.
The thing is in that system there is then no 'grief' in the cloaking. If the rewards scale with time. Too much differentiation between winning makes the environment less casual friendly and less friendly to those who aren't pointed up and trained in pvp.
30 badges versus 18
Currently if you do win and do it quick you DO get better awards and progress faster. However if you can fail spectacularly at machine gun rates you progress fast as well but if you are stuck in good or stalled fights you are at a standstill. Time limits on some matches may be another useful tool.
And yes end of match incentivised MVP awards is another way to encourage participation.